Re-build?!
04-12-2018, 12:15 AM
#1
Racer
Thread Starter
Re-build?!
Hi, kindly check the you tube link (hope it works) for smoke coming from the dipstick tube and also found some oil coming out after driving:
compression Test was done and #8 was low (reading 85). So mechanic said it’s the ring and call for a rebuild.
What do you think? The ride is a 91 auto with 68k on the meter.
and if the engine is coming out for the rebuild what do you suggest for upgrades and mods to put in some HP (bring it close to 12’s or mid 11’s)
Appreciate the feedback
TIA
What do you think? The ride is a 91 auto with 68k on the meter.
and if the engine is coming out for the rebuild what do you suggest for upgrades and mods to put in some HP (bring it close to 12’s or mid 11’s)
Appreciate the feedback
TIA
04-12-2018, 07:08 AM
#3
Racer
Thread Starter
04-13-2018, 11:19 AM
#4
Racer
Thread Starter
If a rebuild is the way to go, is it better to change parts as they come off if required or just go for a full rebuild kit from summit racing for example?
04-13-2018, 11:20 AM
#5
Depending on your budget when the motor goes back in do intake manifold, cam, exhaust, stall and gears and you will see 12s. Add a stroker kit to the rebuild and you'll see mid 11s. Don't for get the tune.
04-13-2018, 11:43 AM
#6
Le Mans Master
Was wet compression test done? Condition of spark plug? A bore scope could show if cylinder walls are scored, requiring overbore. A crate engine with a warranty and is already proven to be over at or above 430 hp maybe a better option.
04-13-2018, 07:16 PM
#7
Melting Slicks
I am surprised nobody has asked if the car has been stored for a long time. Rings can get stiff from sitting and will loosen up and seal when driven. I am more familiar with this with motorcycles stored and then given a compression test. Dan
04-14-2018, 07:04 AM
#8
Racer
Thread Starter
yes the car sat for a while but since i bought it I've been driving it on weekends around the block.
yesterday i started the car and immediately noticed smoke coming from the dipstick tube as in the video above. after a while idling noticed some oil on the exhaust passenger side just under the last spark plug (#8 i think) which caused smoke after burning on the hot exhaust beneath!
i 've put the rebuild on hold for now until I'm sure what to do.
Thoughts?
yesterday i started the car and immediately noticed smoke coming from the dipstick tube as in the video above. after a while idling noticed some oil on the exhaust passenger side just under the last spark plug (#8 i think) which caused smoke after burning on the hot exhaust beneath!
i 've put the rebuild on hold for now until I'm sure what to do.
Thoughts?
04-14-2018, 08:08 AM
#9
Melting Slicks
Driving around the block will not be enough. It sounds to me that you may have two unconnected problems. If you get a leakdown test it will tell you if it is the rings or a valve. If it is the rings here is what I would do (some may disagree). I would remove the plug and put in maybe two ounces of Kroil penetrating oil and let sit for a few days or longer. I would put in another couple of ounces a few days later. Wait a few more days. I would then tape a small clear plastic tube to my shop vac and remove any residual oil. I would then pull the coil wire so it can't start and spin the engine with the starter to shoot out any left. I would then wait a few days for any kroil left to seep down. Put back in the plug and drive. I would drive fast as possible. The oil leak you mentioned is probably not connected.
Last edited by Whaleman; 04-14-2018 at 08:32 AM.
04-15-2018, 08:16 PM
#10
Le Mans Master
Member Since: Oct 2002
Location: Las Vegas - Just stop perpetuating myths please.
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Driving around the block will not be enough. It sounds to me that you may have two unconnected problems. If you get a leakdown test it will tell you if it is the rings or a valve. If it is the rings here is what I would do (some may disagree). I would remove the plug and put in maybe two ounces of Kroil penetrating oil and let sit for a few days or longer. I would put in another couple of ounces a few days later. Wait a few more days. I would then tape a small clear plastic tube to my shop vac and remove any residual oil. I would then pull the coil wire so it can't start and spin the engine with the starter to shoot out any left. I would then wait a few days for any kroil left to seep down. Put back in the plug and drive. I would drive fast as possible. The oil leak you mentioned is probably not connected.
Thats very low mileage for worn rings. Check the spark plug for color. Verify with L/D test not the valves. FWIW you can drive the car with low compression for a long long time. My LT1 camaro ran just fine with #8 50psi lower than the rest. And you can find plenty of rebuild-able GEN II LT1 cores for a song to rebuild while you can drive the car as is.
Good luck.
04-15-2018, 11:54 PM
#11
Racer
Thread Starter
Thanks for the advice guys, much appreciated.
I think first I need to find out where the leak is coming from. I’ll remove the plug and see.
What should I be looking for once plugs are out? Is it normal to have an oil leak from plugs? Forgive my many questions im trying to DIY... don’t completely trust the mechanics over here!!
Once that issue is fixed, I’ll do the leak down test .. which I require you help again guys to do that myself if it’s easy enough
I think first I need to find out where the leak is coming from. I’ll remove the plug and see.
What should I be looking for once plugs are out? Is it normal to have an oil leak from plugs? Forgive my many questions im trying to DIY... don’t completely trust the mechanics over here!!
Once that issue is fixed, I’ll do the leak down test .. which I require you help again guys to do that myself if it’s easy enough
04-16-2018, 12:21 AM
#12
Le Mans Master
Member Since: Oct 2002
Location: Las Vegas - Just stop perpetuating myths please.
Posts: 7,098
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If you have bad ring seal you should see a lot of black soot on the plug. I would assume thats from the cylinder with low cranking pressure.
04-16-2018, 06:18 AM
#13
Melting Slicks
The one way one cylinders rings can wear at low mileage is if the car is driven hundreds or thousands of miles with one cylinder not firing and the gas washing off the oil on that cylinders wall. I have seen this once. Oil can't leak out a plug. Dan
04-29-2018, 04:42 AM
#14
Racer
Thread Starter
Hi all, ok I decided to go for a complete rebuild and have it modified. So I need your experience and expert inputs on this specially if anyone done the same:
First: the rebuild: I’m lookimg for a complete rebuild kit (all forged) that includes pistons, rings, rods...etc I found some at Summit but can’t tell which is compatible with my stock base? Practical real life experience on this would be very helpful. Or should I go ordering parts separately??!
Second: the Mods: so far I’m looking to get the following:
- Hooker LT headers (2149)
- Borla cat back exhaust dual 3’’ (does it require y or x pipe or straight duals?)
- AFR 195cc Heads (what’s cylinders chamber cc?)
- LPE 219 or zz4 (which is better?)
- 1.6 RR (scorpion or magnum?) will these fit the stock valve cover?
- FIRST TPI intake (or ther brands if better)
- 24# injectors
any other parts to consider with the above?
Last: the output: what would be the expected gain with the above interms of rwhp & torque. the vette is for weekend fun and street race from time to time. Might try a pass or two at the strip.
Appreciate your valuable feedback
TIA
First: the rebuild: I’m lookimg for a complete rebuild kit (all forged) that includes pistons, rings, rods...etc I found some at Summit but can’t tell which is compatible with my stock base? Practical real life experience on this would be very helpful. Or should I go ordering parts separately??!
Second: the Mods: so far I’m looking to get the following:
- Hooker LT headers (2149)
- Borla cat back exhaust dual 3’’ (does it require y or x pipe or straight duals?)
- AFR 195cc Heads (what’s cylinders chamber cc?)
- LPE 219 or zz4 (which is better?)
- 1.6 RR (scorpion or magnum?) will these fit the stock valve cover?
- FIRST TPI intake (or ther brands if better)
- 24# injectors
any other parts to consider with the above?
Last: the output: what would be the expected gain with the above interms of rwhp & torque. the vette is for weekend fun and street race from time to time. Might try a pass or two at the strip.
Appreciate your valuable feedback
TIA
04-29-2018, 07:53 AM
#15
Le Mans Master
The stock tpi intake will be the performance limiter. You will need an aftermarket intake. Tuning will be the other major expense. You may want to investigate your options. You can opt to go carb if you're stuck during the tuning phase.
04-29-2018, 02:19 PM
#16
Melting Slicks
68 K and time for a rebuild? That's ridiculous.
Check the valve train on the #8 cylinder; on my engine the #8 rocker arm was off the valve stem, the cam lobe was wiped and associated lifter roller was ruined. Replacing the cam and lifters was a lot, lot cheaper than a rebuild.
After checking out the valve train, try a wet and a dry compression test, and a leakdown test. If the compression is still low, well then consider pulling the head and finding out whats going on in the #8 cylinder.
p.s. find a new mechanic who isn't quite so willing to spend your money. and maybe knows a little more about trouble shooting engines,
Check the valve train on the #8 cylinder; on my engine the #8 rocker arm was off the valve stem, the cam lobe was wiped and associated lifter roller was ruined. Replacing the cam and lifters was a lot, lot cheaper than a rebuild.
After checking out the valve train, try a wet and a dry compression test, and a leakdown test. If the compression is still low, well then consider pulling the head and finding out whats going on in the #8 cylinder.
p.s. find a new mechanic who isn't quite so willing to spend your money. and maybe knows a little more about trouble shooting engines,
04-29-2018, 04:46 PM
#17
Le Mans Master
Member Since: Oct 2002
Location: Las Vegas - Just stop perpetuating myths please.
Posts: 7,098
Received 373 Likes
on
356 Posts
68 K and time for a rebuild? That's ridiculous.
Check the valve train on the #8 cylinder; on my engine the #8 rocker arm was off the valve stem, the cam lobe was wiped and associated lifter roller was ruined. Replacing the cam and lifters was a lot, lot cheaper than a rebuild.
After checking out the valve train, try a wet and a dry compression test, and a leakdown test. If the compression is still low, well then consider pulling the head and finding out whats going on in the #8 cylinder.
p.s. find a new mechanic who isn't quite so willing to spend your money. and maybe knows a little more about trouble shooting engines,
Check the valve train on the #8 cylinder; on my engine the #8 rocker arm was off the valve stem, the cam lobe was wiped and associated lifter roller was ruined. Replacing the cam and lifters was a lot, lot cheaper than a rebuild.
After checking out the valve train, try a wet and a dry compression test, and a leakdown test. If the compression is still low, well then consider pulling the head and finding out whats going on in the #8 cylinder.
p.s. find a new mechanic who isn't quite so willing to spend your money. and maybe knows a little more about trouble shooting engines,
I think you are going to create a garage statue that won't move for years and years. On top of rebuilding you need to learn how to tune the motor for all those mods. Just my advice is one step at a time unless the motor is truly busted.
04-29-2018, 11:29 PM
#19
Racer
Thread Starter
68 K and time for a rebuild? That's ridiculous.
Check the valve train on the #8 cylinder; on my engine the #8 rocker arm was off the valve stem, the cam lobe was wiped and associated lifter roller was ruined. Replacing the cam and lifters was a lot, lot cheaper than a rebuild.
After checking out the valve train, try a wet and a dry compression test, and a leakdown test. If the compression is still low, well then consider pulling the head and finding out whats going on in the #8 cylinder.
p.s. find a new mechanic who isn't quite so willing to spend your money. and maybe knows a little more about trouble shooting engines,
Check the valve train on the #8 cylinder; on my engine the #8 rocker arm was off the valve stem, the cam lobe was wiped and associated lifter roller was ruined. Replacing the cam and lifters was a lot, lot cheaper than a rebuild.
After checking out the valve train, try a wet and a dry compression test, and a leakdown test. If the compression is still low, well then consider pulling the head and finding out whats going on in the #8 cylinder.
p.s. find a new mechanic who isn't quite so willing to spend your money. and maybe knows a little more about trouble shooting engines,
it’s been garaged for a while now.And either way I want to modify it and beef it up with the above set up. Now if a rebuild is not required I’m Happyyyy!! I’ll save that cost for more mods.
04-29-2018, 11:33 PM
#20
Racer
Thread Starter
I think the motor is fine, and was running great and still That’s why I was planning for the mods for a while now until this issue started!!